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91.
Cyclooxygenase‐2 (COX‐2) is overexpressed in several human and animal neoplasms, including the human endometrial carcinoma. It has been suggested as a prognostic marker and a potential therapeutic target. This study aimed to (i) clarify histological aspects of feline endometrial adenocarcinomas (FEA) of the papillary serous type and (ii) characterize COX‐2 immunohistochemical expression in normal, hyperplastic and neoplastic endometrium in this species. Archived paraffin‐embedded tissue samples of 33 FEA, eight cystic endometrial hyperplasias (CEHs) and 21 samples of normal, healthy endometrium in the follicular (FS; n = 10) and luteal (LS; n = 11) stages were evaluated. Histological evaluation of haematoxylin and eosin‐stained sections of the FEA revealed a papillary proliferation of neoplastic cells of serous type, accompanied by clear and multinucleated cells. Other architectural arrangements mainly included solid and tubular growth. Randomly distributed areas of necrosis within the tumours were commonly observed. Invasion of the myometrium, of the serosa and of the vascular and/or lymphatic vessels was not constant features. The mean number of mitoses was higher in FEA compared to non‐neoplastic endometrium. COX‐2 scores were lower in FEA (p = 0.003) and CEH (p = 0.05) when compared to normal epithelium (NE). The loss of the membrane apical reinforcement in epithelial cells was observed in FEA samples, which was accompanied by the dislocation of COX‐2 labelling into the cytoplasm and the perinuclear area; in contrast, in epithelial cells in the healthy and hyperplastic endometria, the immunoreaction showed the characteristic pattern of apical membrane reinforcement, suggestive of the membrane polarization. COX‐2 epithelial scores were higher in the FS than in the LS. No differences were found in stromal COX‐2 expression between normal, CEH and FEA groups, but it was higher in the LS than in the FS. In summary, loss of COX‐2 compartmentalization in neoplastic epithelial cells might be one of the molecular events underlying endometrial carcinogenesis.  相似文献   
92.
Because of instrumental sensitivity limits and stellar distances, the types of x-ray flares observable on stars have been intrinsically much more energetic than those on the sun. Such enormous events are a useful extrapolation of the solar phenomenon if the underlying assumption is correct that they form a continuous sequence involving similar physical processes as on the sun. The Advanced Satellite for Cosmology and Astrophysics (ASCA), with its greater sensitivity and high-energy response, is now able to test this hypothesis. Direct comparison with solar flares measured by the x-ray-monitoring Geostationary Operational Environmental Satellites (GOES) is possible. The detection of flares on Proxima Centauri that correspond to GOES M-class events on the sun are reported.  相似文献   
93.
Plant Foods for Human Nutrition - The consumption of sprouts has increased as the germination process causes changes in the chemical composition of the seeds, improving their nutritional value. The...  相似文献   
94.
An 8-year-old mare, with a foal at foot, was inseminated on foal heat with frozen semen, with the resultant pregnancy lost between days 34 and 41. The right ovary developed a large anovulatory follicle that was non-responsive to multiple doses of ovulating agents. The follicle eventually appeared to luteinise, although plasma progesterone concentrations did not reflect this. Another follicle developed, responded to GnRH and resulted in a pregnancy from frozen semen that went to term with a healthy foal. When the mare was examined after foaling, the structure on the right ovary appeared to be a granulosa cell tumour; the left ovary was smaller than normal and non-functional. Surgical removal of the right ovary before increasing photoperiod resulted in a return to function of the left ovary and a pregnancy to frozen semen on the second cycle following removal. Figures showing concentrations of inhibin, progesterone, androstenedione, oestradiol and testosterone are presented for this entire period. Unusual ovarian activity in the mare might be a prelude to the development of a granulosa cell tumour.  相似文献   
95.
Gluten is an important protein complex for baking products found in wheat, rye, barley, and some oat varieties. However, some people need to avoid these grains and their products because they result in gluten‐related disorders. The only treatment for these individuals is to engage in a gluten‐free diet. The objective of this work was to verify if the gluten content of several commercial food products sold in Brazil complied with their labeling. The Méndez ELISA R5 sandwich method was used to analyze 437 samples, and of these, 70% were labeled as gluten‐free, 26% as containing gluten, and 4% not labeled in relation to gluten. The results indicated that 89% of the products labeled as gluten‐free were correctly labeled and 11% were not, which represented a risk for celiac people.  相似文献   
96.
Cryptococcal meningitis in an alpaca   总被引:1,自引:0,他引:1  
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97.
Otoliths of glass eels and larvae collected from the Rio Minho (Portugal/Spain) as well as from the Iberian continental slope from the Bay of Biscay were analyzed by scanning electron microscopy. Preliminary data are presented on the total radius of the otolith and the width of the zone exhibiting a diffuse structure which, in the literature, is suggested to be the zone of metamorphosis. It was found that the radius increased from the development stage I through stage II to the glass eel stage (Vb). The width of the diffuse zone also exhibited an increase. Calculations of the dimensions of the diffuse zone of specimens older than stage I revealed that the area of metamorphosis amounts to about 28–60% of the total diffuse zone. From these results it is evident that part of the diffuse zone must have formed during a larval phase of retarded growth, during which no formation of daily growth rings takes place. Only the outer portion of the diffuse zone can be accounted for by the metamorphosis. For these reasons, an exact age determination by counting daily rings seems impossible. A determination of the oceanic life of the eel recruits is difficult for other reasons too: all earlier and recent studies have indicated that Anguilla leptocephali and their metamorphosis stages do not occur on the continental shelf, which could add an additionally high amount of time needed until arrival at the coasts.  相似文献   
98.
Eight pregnant goats were inoculated orally with 10 to 1,000 oocysts of Toxoplasma gondii at 83 to 102 days of gestation. Serum samples from the goats and from the kids born to them were analyzed, using the Sabin-Feldman dye test (DT), a commercially available modified agglutination test (MAT), and a latex agglutination test. Six of the does were observed for greater than 1 year; during this time, they delivered twice. All does developed DT and MAT antibody titers of greater than or equal to 1:2,048 within 29 days after inoculation, and the high titers persisted through the 2nd pregnancy; therefore, serologic results alone should not be relied on for the diagnosis of T gondii-induced abortion in does. On the other hand, all transplacentally infected kids had DT or MAT antibody titers of 1:2,048 before ingesting colostrum, indicating the usefulness of serologic evaluation of the fetus or stillborn kid in the diagnosis of abortion. Antibody was not found in the sera of noninfected kids born to Toxoplasma-infected does. The passively acquired colostral antibody declined by 5 months. Therefore, specific antibody found in adult goats is probably actively acquired. The commercially available MAT was simple, sensitive, and reliable for the diagnosis of caprine toxoplasmosis. The latex agglutination test needs further improvement, as titers rarely exceeded 1:256.  相似文献   
99.
Bovine herpesvirus type 5 (BoHV-5) is the causative agent of bovine herpetic encephalitis. In countries where BoHV-5 is prevalent, attempts to vaccinate cattle to prevent clinical signs from BoHV-5-induced disease have relied essentially on vaccination with BoHV-1 vaccines. However, such practice has been shown not to confer full protection to BoHV-5 challenge. In the present study, an inactivated, oil adjuvanted vaccine prepared with a recombinant BoHV-5 from which the genes coding for glycoprotein I (gI), glycoprotein E (gE) and membrane protein US9 were deleted (BoHV-5 gI/gE/US9), was evaluated in cattle in a vaccination/challenge experiment. The vaccine was prepared from a virus suspension containing a pre-inactivation antigenic mass equivalent to 107.69 TCID50/dose. Three mL of the inactivated vaccine were administered subcutaneously to eight calves serologically negative for BoHV-5 (vaccinated group). Four other calves were mock-vaccinated with an equivalent preparation without viral antigens (control group). Both groups were boostered 28 days later. Neither clinical signs of disease nor adverse effects were observed during or after vaccination. A specific serological response, revealed by the development of neutralizing antibodies, was detected in all vaccinated animals after the first dose of vaccine, whereas control animals remained seronegative. Calves were subsequently challenged on day 77 post-vaccination (pv) with 109.25 TCID50 of the wild-type BoHV-5 (parental strain EVI 88/95). After challenge, vaccinated cattle displayed mild signs of respiratory disease, whereas the control group developed respiratory disease and severe encephalitis, which led to culling of 2/4 calves. Searches for viral DNA in the central nervous system (CNS) of vaccinated calves indicated that wild-type BoHV-5 did not replicate, whereas in CNS tissues of calves on the control group, viral DNA was widely distributed. BoHV-5 shedding in nasal secretions was significantly lower in vaccinated calves than in the control group on days 2, 3, 4 and 6 post-challenge (pc). In addition, the duration of virus shedding was significantly shorter in the vaccinated (7 days) than in controls (12 days). Attempts to reactivate latent infection by administration of dexamethasone at 147 days pv led to recrudescence of mild signs of respiratory disease in both vaccinated and control groups. Infectious virus shedding in nasal secretions was detected at reactivation and was significantly lower in vaccinated cattle than in controls on days 11–13 post-reactivation (pr). It is concluded that the inactivated vaccine prepared with the BoHV-5 gI/gE/US9 recombinant was capable of conferring protection to encephalitis when vaccinated cattle were challenged with a large infectious dose of the parental wild type BoHV-5. However, it did not avoid the establishment of latency nor impeded dexamethasone-induced reactivation of the virus, despite a significant reduction in virus shedding after challenge and at reactivation on vaccinated calves.  相似文献   
100.
It is important to get mares pregnant as early as possible after vernal transition and thus, identification signs of impending 1st ovulation of the year are warranted. To identify clinical indicators of an approaching first ovulation of the year, mares were teased with a stallion for oestrous detection starting January 3 and subjected to ultrasonographic examination. Day of first appearance of uterus oedema, follicular wall invagination, intrafollicular echogenicity, double contour of the follicle wall, increase in granulosa thickness, follicular wall hyperechogenicity and appearance of pear‐shaped follicles was registered, as well as follicle diameter and number. Seventy per cent of the mares had anovulatory oestrous periods of 4.6 ± 3.6 days, with an interoestroual interval of 12.5 ± 12.2 days. Number of anovulatory oestruses per mare was 2.4 ± 2.3. Uterine oedema occurred in 77% of the mares, 32.4 ± 25.6 days before ovulation. Invagination of the follicular wall appeared in 44.4% of the animals, 24.5 ± 18.4 days before ovulation. Intrafollicular echogenicity was seen in all mares and double contour of the follicle was seen in 77% of the animals. Both last two characteristics appeared 1–72 days before ovulation. Increased thickness of the granulosa occurred in 66% of the mares, 1–19 days before ovulation. Pear‐shaped follicles and follicular wall hyperechogenicity were detected 3 or less days before the first ovulation, in 44.4% and 55.5% of mares, respectively. Mean number of follicles >15 mm decreased at least 16 days before ovulation. We concluded that no isolated characteristic was a reliable indicator. However, increase in granulosa thickness, formation of a pear‐shaped follicle and follicular wall hyperechogenicity, associated with the reduction of the number of follicles >15 mm in diameter to <3, resulted in the first ovulation of the year in 44–67% of the transitional mares, 1–19 days after the characteristics appeared.  相似文献   
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